Endoscopic system with a solid-state light source

ABSTRACT

An endoscopic system for internal inspection of an object includes an endoscope extending along a longitudinal axis between a distal end to be inserted into the object and a proximal end and an illumination assembly attached to the proximal end of the endoscope. The illumination assembly includes a solid-state light source. The endoscopic system also includes an optical system positioned distally from the solid-state light source to receive and convey light to the distal end.

TECHNICAL FIELD

[0001] This invention relates to endoscopic systems with illuminationsources.

BACKGROUND

[0002] Light sources are used in endoscopy (e.g., medical, industrial).Medical endoscopes are used to inspect regions within the body (e.g.,cavities, joints) during surgery (such as laparoscopic/thoracoscopicsurgery) through a small puncture. Typically, the endoscope includes arigid or flexible elongated insertion tube equipped with a set ofoptical fibers that extend from a proximal handle through the insertiontube to the distal viewing tip of the endoscope. An external lightsource provides light to the optical fibers via a cable that attaches tothe handle (e.g., at a post on the side of the handle) of the endoscope.

SUMMARY

[0003] The invention is related to an endoscopic system for internalinspection of an object.

[0004] In a general aspect of the invention, the endoscopic systemincludes an endoscope, an illumination assembly attached to the proximalend of the endoscope and having a solid-state light source, and anoptical system positioned distally from the solid-state light source toreceive and convey light to the distal end. The endoscope extends alonga longitudinal axis between a distal end to be inserted into the objectand a proximal end.

[0005] Embodiments of this aspect of the invention may include one ormore of the following features.

[0006] The solid-state light source includes semiconductor light sources(e.g., light emitting diodes (LEDs)).

[0007] The solid-state light source includes a hollow shaft having alongitudinal axis and a set of ribs positioned along a periphery of theshaft, each rib having a first side and a second side. The ribs extendalong the longitudinal axis of the shaft and are symmetrically spacedaround the periphery of the shaft. The first side of each rib has atleast one LED and the second side of each rib has at least one LED.

[0008] Alternatively, each rib is axially spaced along the longitudinalaxis of the shaft. Each rib has at least two LEDs spaced symmetrical onthe first side of each rib. The LEDs are grouped in a trio, each triohas a first LED configured to emit a blue light, a second LED configureto emit a red light, and a third LtD configured to emit a green light.

[0009] The optical system includes a set of fiber optic elements, eachsemiconductor light source is configured to emit light to at least onecorresponding fiber optic element.

[0010] The endoscopic system can further include a camera systemproximally positioned to the optical system and a focusing system.

[0011] The endoscope is removable and replaceable from the illuminationassembly and can further include an eyepiece positioned proximally tothe optical system. The endoscope includes a light post, the set offiber optic elements connecting the solid-state light source to thelight post.

[0012] The light post is positioned to receive light at an angle to thelongitudinal axis.

[0013] The endoscopic system further includes a wireless transmitterpositioned proximally from the distal end of the endoscope and a batterypositioned proximally to the distal end of the endoscope. The endoscopeincludes an image sensor, for example, positioned proximally to theendoscope.

[0014] The endoscope is configured to rotate about the longitudinal axisof the elongated member relative to the stationary imaging sensor.

[0015] In another aspect of the invention, the endoscopic systemincludes an endoscope extending along a longitudinal axis between adistal end to be inserted into the object and a proximal end and asolid-state light source positioned at the endoscope.

[0016] Embodiments of this aspect of the invention may include one ormore of the following features. The solid-state light source ispositioned in the distal end of the endoscope. Alternatively, thesolid-state light source is positioned at the proximal end of theendoscope. For example, the solid state light source can be enclosedwithin a handle portion of the endoscope or as a unit integrallyattached to a housing at the proximal end of the endoscope.

[0017] Among other advantages, the solid-state light source concentrateslight in a small area while providing high luminous emittance. Also, thesemiconductor light source more efficiently couples light energy into anoptical element (e.g., optic fiber). In general, the solid-state lightsource is compact and consumes less power. In addition, the solid-statelight source responds to changes in applied voltage more quickly than anincandescent lamp or an arc lamp.

[0018] The necessity of having a separate light source box and a lightguide connected to the scope is eliminated. This greatly improves theuser's comfort and ease in maneuvering the device as there is no longera heavy light guide attached to the scope. A combination of a wirelesscamera and an endoscope with a built-in solid-state light source willrender a completely self-contained wireless endoscope.

DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is a block diagram of an endoscopic system having asolid-state light source attached to an endoscope.

[0020]FIG. 2 is a cross-sectional side view of the endoscope, anillumination assembly, and a video camera assembly.

[0021]FIG. 3A is a perspective view of a light source/fiber subassembly.

[0022]FIG. 3B is an end view of the solid-state light source/fibersubassembly taken along the line 3B-3B.

[0023]FIG. 4A is a cross-sectional view of another embodiment of thelight source/fiber subassembly having ribs axially spaced.

[0024]FIG. 4B is an end view taken along lines 4B-4B of FIG. 4A.

[0025]FIG. 5A is a cross-sectional view of another embodiment of thesolid-state light source assembly having additional space for fiberoptic lines.

[0026]FIG. 5B is an end view taken along lines 5B-5B of FIG. 5A.

[0027]FIG. 6 is cross-sectional view of the endoscope with an eyepiece.

[0028]FIG. 7 is a cross-sectional view of another embodiment of theendoscope and the solid-sate light source assembly with an exteriorlight post fitting.

[0029]FIG. 8 is a cross-sectional view of an embodiment of a solid-statelight source located in a distal end of the endoscope.

[0030]FIG. 9 is a cross-sectional view of an embodiment of a solid-statelight source in an electronic endoscope having a distal imager.

DETAILED DESCRIPTION

[0031] Referring to FIG. 1, an endoscopic system 10 includes anendoscope 42 having a rigid insertion section 16 and a proximal body 64.Endoscopic system 10 also includes an illumination assembly 26 connectedto proximal body 64 of endoscope 42. As will be explained in greaterdetail, illumination assembly 26 includes a solid-state light sourceassembly 44 (FIG. 2) for generating white light that is conveyed to aworking area 24 via insertion section 16. Illumination assembly 26 alsoencloses a focusing assembly 46 (FIG. 2) used to provide focused imagesfrom working area 24 to a video camera assembly 48. Illuminationassembly 26 serves as a portion of the endoscopic system 10 used by asurgeon to hold and manipulate endoscope 42 at working area 24. Videocamera assembly 48 is connected to illumination assembly 26 andtransmits video signals representative of images at working area 24 fordisplay on video monitor 18 thru cable 14.

[0032] Referring to FIG. 2, solid-state light assembly 44 providesillumination to working area 24 from multiple LEDs 100 through a seriesof fiber optic connections (e.g. fiber optic bundle 72, fiber optic line84). The illuminated images from working area 24 are conveyed to cameraassembly 48 through an optical path. The optical path extends fromdistal end 22 through an optical train 66 in endoscope 42 through a setof focusing optics 32 in focusing assembly 46 to video camera assembly48. Adjusting focusing optics 32 focuses the illuminated images.

[0033] Endoscope 42 is an interchangeable component of endoscopic system10 which can be interchanged with endoscopes of other configurations. Inthis embodiment, insertion section 16 is rigid and has a direction ofview offset from a longitudinal axis 34 of the insertion section. Asstated above, endoscope 42 contains fixed optics 68 which can include asingle lens or a group of lenses situated after a field stop. Endoscope42 also includes a proximal window 70 hermetically sealed with a channel67 to prevent the introduction of containments from the environmentincluding the remaining portions of endoscopic system 10 (e.g.,solid-state light source assembly 44).

[0034] A fiber optic bundle 72 conveys light extends through endoscope42 and conveys light from solid-state light source assembly 44 to distalend 22 of the endoscope. At the interface of solid-state light source44, fiber optic bundle 72 is epoxied into a bushing 78, thereby creatinga hermetic seal. In turn, bushing 78 is fixed to proximal body 64 thatis also hermetically sealed.

[0035] Optics train 66 includes fixed optics 68 and proximal window 70positioned near solid-state light source assembly 44. Likewise,solid-state light source assembly 44 includes a front window 47 and alight coupling element 81 both of which are hermetically sealed to ahousing 50. Thus, endoscope 42 and solid-state light source assembly 44are independently hermetically sealed, so that other endoscopes may beremovably attached to solid-state light source assembly 44 (e.g.,flexible endoscopes).

[0036] Solid-state light assembly 44 includes a light source/fiber opticassembly 52 positioned within housing 50 having a hollow shaft 62aligned with longitudinal axis 34.

[0037] Referring to FIGS. 3A and 3B, light source/fiber opticsubassembly 52 includes a metal frame 80, light source assemblies 82,fiber optic lines 84 and a fiber output fitting 86. Frame 80 includes ahollow shaft 88 with axial ribs 90 and a flange 92. In this embodiment,there are four axial ribs 90 symmetrically arranged along thecircumference of hollow shaft 88. Each rib 90 extends the length ofhollow shaft 88. Each side of rib 90 has a mounting face for placinglight source assemblies 82 so that two light assemblies are mounted perrib.

[0038] Within each light source assembly 82 are light emitting diodes(LEDs) 100. Light emitted by each LED 100 is coupled into acorresponding fiber line 84. From each LED 100, corresponding fiberoptic lines 84 are all brought together into a common bundle 94 at adistal end 120 of light source/fiber subassembly 52 where the commonbundle is received and bonded into fiber output fitting 86. A distal end95 of common bundle 94 is fine polished in order to create an interfacefor conveying light into fiber optic bundle 72 located within endoscope42. As explained below, electric power is provided to LEDs 100 by anelectrical connection through a rotational joint 160. The electricalconnection includes an insulated wire 20 connected to a power source(not shown) in video camera assembly 48. The electrical connection alsoincludes a wire lead 113 connected to light source/fiber subassembly 52.

[0039] An axial space 96 between ribs 90 and flange 92 allows for fiberoptic lines 84 coming from different ribs to wrap around the distal partof shaft 88 in order to connect with end fitting 86. A light couplingelement 81 is placed at polished distal end of bundle 94. Thus, whenlight source/fiber subassembly 52 is placed within endoscope 42, lightcoupling element 81 may interface the polished proximal end of fiberoptic bundle 72. Therefore, emitted light from solid-state light sourceassembly 44 can pass through insertion section 16 to working area 24.

[0040] As light source/fiber subassembly 52 is inserted into housing 50,the inside diameter of the hollow shaft 80 of the subassembly slidesover the outer diameter of hollow shaft 62. The end of light couplingelement 81 is brought into contact with the proximal face of fiber opticbundle 72. Light source/fiber subassembly 52 is secured to housing 50 byattaching rear flange 56 to the open proximal end of the housing 50 bythreads. An insulating ring 58, made of an electrically insulatingmaterial (e.g., ceramic, plastic), is securely attached to rear flange56 (e.g., by press fitting, bonding or other fastening method). Acontact ring 60, made of a high electrical conductor (e.g., copper), isembedded into the insulating ring 58. Insulated wire lead 113 has oneend soldered to the contact ring 60 at one end and an opposite endconnected to a positive bus 114 of one of the light source assemblies82. Each of the light source assemblies 82 includes positive bus 114which are all interconnected by wires 98. Each of the light sourceassemblies includes a negative buses 115, each connected to the metalframe 80 which serves as a common ground.

[0041] In this embodiment, LEDs 100 are square, approximately 1 mm perside. LEDs 100 emit a blue light. A phosphor layer (not shown) isapplied between the LED emitting surface and the entrance face of fiberlines 84. When the blue light passes through the phosphor layer, theblue light excites the phosphor layer causing it to fluoresce green andred light. The green light, red light and blue light together form whitelight. In other embodiments, LEDs 100 emit ultraviolet light. In stillother embodiments, the phosphor layer can be located anywhere along anillumination path of the light (e.g., at an interface of light couplingelement 81 and fiber bundle 72 or at distal end 22 of endoscope 42).LEDs 100 suitable for use in this embodiment of solid-state sourceassembly 44 can be obtained from Lumileds Lighting of San Jose, Calif.Loose fibers, suitable for this embodiment, can be obtained bySchott-Fostec, LLC of Auburn, N.Y.

[0042] Referring back to FIG. 2, focusing assembly 46 includes a frontportion 36, a focusing ring 38, a contact pin assembly 40, a retainernut 125, a washer 124, and a lens cell 123 with a focusing lens 32, afocusing sleeve 130, and a lens body 132. Retainer nut 125 is secured tohollow shaft 62 of housing 50 by threads. Low friction washer 124 isplaced between nut 125 and front portion 36. Front portion 36 includes aseal 159, e.g., a low drag rubber-like seal. Seal 159 may be in theshape of an O-ring or an X-shaped Quad ring. As nut 125 is threaded ontoshaft 62, the nut holds together the solid-state light source assembly44 and front portion 36 of the focusing assembly 46. The distal end ofthe front portion 36 abuts the proximal end of rear flange 56 therebydefining rotational joint 160. A lubricant (e.g., high vacuum greaseavailable from Dow Corning Corporation) is applied to seal 159 to ensureits proper functioning.

[0043] Solid-state light source housing 50 has a ridge 108 forconvenient rotation. In operation, when the user applies a tangentialforce to ridge 108, the entire solid-state light source assembly 44rotates relative to front portion 36 of focusing assembly 46. Retainingnut 125 and washer 124 also rotate with solid-state light sourceassembly 46. An axial alignment between solid-state light sourceassembly 44 and focusing assembly 46 is maintained by closely providinga tolerance to an interior bearing surface 161 of the front portion 36and an exterior bearing surface 162 of hollow shaft 62.

[0044] Preferably, front portion 36 and shaft 62 are made from differentmaterials, any combination of which produces low friction. The torquerequired for rotation is determined by frictional forces between theseal 159 and rear flange 56, between interior bearing surfaces 161 andexterior bearing surface 162, and between washer 124 and contacting itsurfaces of the nut 125 and front portion 36. The suitable amount oftorque is set by applying a proper pressure when nut 125 is threadedover shaft 62. When a specified amount of torque is reached, nut 125 islocked in place using known methods (e.g., with retaining compoundsavailable from Loktite Corp. applied to the threads). An additionalO-ring (or multiple O-rings) 163 may be provided for the torqueadjustment and additional seal.

[0045] With endoscope 42 locked to solid-state light source assembly 44,rotational joint 160 allows for rotation of endoscope 42 around axis 34.Focusing sleeve 130 is surrounded by focusing ring 38 and secured to itby threads, for example. Lens body 132 is attached to front portion 36preferably by threads. The proximal part of the lens body 132 may act asa front flange of the video camera assembly 48. The distal end offocusing ring 38 abuts the proximal end of the front portion 36 in asealed relationship. Similarly, the proximal end of focusing ring 38abuts the distal end of the lens body 132 in a sealed relationship. Thedynamic seals 126 and 127 are constructed similarly to the seal 159.Lens cell 123 carries focusing lenses 32 for projecting the image ontothe surface of the image pickup device 133.

[0046] A cam screw 131 secures lens body 132, the focusing sleeve 130,and the lens cell 123 together. Focusing sleeve 130 includes a helicalthrough slot 164 whose axial length corresponds to the required range oflens cell axial movement for proper focusing. Helical slot 164 receivesthe upper part of the head of cam screw 131. Lens body 132 includes anaxial slot 137 that receives the lower part of the head of cam screw131. The length of slot 137 also corresponds to the focusing range oflens cell 123. As focusing ring 38 rotates, focusing sleeve 130 beingsecurely attached to the ring also rotates. The head of cam screw 131rides inside helical slot 164 and inside axial slot 137. Axial componentof the helix causes back-and-forth movements of cam screw 131 dependingon the direction of rotation of the focusing ring 38. Axial slot 137prevents rotation of cam screw 131 ensuring only axial motion. As camscrew 131 is securely attached to the lens cell 138, the lens cell 138will also move axially within limits of the axial length of helical slot64 and the length of slot 137.

[0047] Front portion 36 also includes contact pin assembly 40 whichincludes a sleeve 165 made out of an electrically insulating material.Contact pin assembly 40 is securely attached to front portion 36 so thecontact pin assembly is situated opposite to the contact ring 60 of thesolid-state light source assembly 44. A small compression spring 167 issecured inside sleeve 165 (e.g., flared in) so that the compressionspring exerts a force onto a conductive pin 166 bringing the pin into afirm contact with contact ring 60. Insulated wire lead 20 is soldered toproximal end of pin 166 and follows through a slot 138 made in lens cell123 into video camera assembly 48 where the wire lead is connected tothe appropriate circuitry for providing the proper voltage level tolight sources 100.

[0048] Video camera assembly 48 includes an image pickup device 133(e.g. CCD or CMOS sensor), a housing 168, and an electric cable 136. Inoperation, the camera head normally is not rotated and is held so thatimage pickup 133 is maintained in the right-side-up position. Bymaintaining the right-side-up position regardless of the rotation of theendoscope, the proper orientation of the image is always attained.Normally, camera heads have a protruding feature 134, (e.g. buttons,ridges, etc.) on their top sides giving the user a tactile feeling ofthe right side up position. Electric cable 136 connects the camera headto a camera control unit (not shown) containing a power supply, a cameramotherboard and various auxiliary circuitry for imaging. In otherembodiments, video camera assembly 48 contains a battery and all thecircuitry necessary to transmit video images to video monitor 18.

[0049] In other embodiments, light coupling element 81 may be eitheromitted altogether or the coupling element may be a part of endoscope 42by being built into fitting 78. In other embodiments, light couplingelement 81 may be attached securely to fitting 86. Light couplingelement 81 may be a solid or fiber-optic cone which matches theNumerical Aperture (NA) of bundle 94 and fiber optic bundle 72. In otherembodiments, a mixing rod with a square or hexagonal cross-section isused to provide uniform white when using multiple colored LEDs as alight source.

[0050] Referring to FIGS. 4A and 4B, in other embodiments, there are anumber of configurations of the light source/fiber subassembly that arepossible. In one embodiment, ribs 202 can be arranged radially so thatlight sources 200 are situated in a ring fashion on each radial rib.Openings 203 are provided in the distal ribs for the passage of thefiber lines 201 from the proximally located light sources.

[0051] In the preferred embodiment (FIG. 2) there is only one contactring and one pin assembly for the positive voltage transfer. This issufficient, if the negative buses of the light sources are grounded tothe metal frame, because the frame connects to the camera housing commonground through the housing of the solid-state light source assembly andthe lens cell. Yet, in many embodiments, a separate ground or negativeelectric potential would be required for the negative buses because ofelectrical design considerations. In these embodiments, the contact ringmay be split into two concentric mutually insulated rings so that twopins will be used for the voltage transfer.

[0052] Also, in the preferred embodiment, the arrangement of having thecontact ring and the pin assembly has a potential drawback of havinglimited reliability in the spring-loaded electrical contact and apossibility of electrical shorts if the seal 159 fails. In addition,there is a limited reliability in the spring-loaded electrical contact.

[0053] Referring to FIGS. 5A and 5B, another embodiment eliminates theinsulating ring and the contact ring so that a rear flange 216 becomesone piece. In this configuration, rear flange 216 is constructed so thata gap 270 sufficiently wide is created between the lens body 228 and alight source frame 209. A flexible cable 271 is fixed at the end ofopening 284 in lens body 228 and then a sufficient slack 285 is created.A distal end of cable 271 is connected to a connector 287 situated onlight source frame 209. From connector 287 the appropriate leads aredistributed between the light sources mounted on frame 209. Cable 271can carry as many leads as needed and may be hardwired (soldered) orconnected by pins at both light source and camera ends thus eliminatinga sliding electrical contact. As solid-state light assembly 244 rotates,the slack 285 gets taken out. Rear flange 216 is attached to a fixed pin286 which is received by a circumferential groove 269 made in the lensbody 228. Groove 269 subtending a sufficiently large angle, e.g.,320-330°, both ends of groove 269 define two stops to limit the rotationat rotational joint 260 due to finite length of cable 271. In thisembodiment, there is no continuous rotation at joint 260, but there isenough rotation to utilize the directional properties of the endoscopeand at the same time maintain the correct orientation of the image. Thisembodiment allows one to use as many leads as necessary to be carriedwithin cable 271. This is especially important if multiple single col orLEDs are used for white light generation. Different current levels (andtherefore different voltages) may be applied to different color LEDs foroptimal color temperature of the resulting white light. Thus, multipleleads will be required to power different light sources.

[0054] In other embodiments, the endoscope is integral to thesolid-state light source assembly. In this arrangement, fiber opticlines connected to light sources continue directly into the endoscope.This configuration eliminates interfaces at light coupler therebyincreasing the light efficiency.

[0055] In still other embodiments, the focusing lens and the fixed lensmay be designed in various configurations including having additionalfixed lens groups securely attached to the camera housing or to anyother parts of the camera head.

[0056] In another embodiment, the video camera assembly includes notjust the camera head, but also rather a self-contained camera which alsoincludes a battery and a wireless transmitter to transmit the videosignal to the TV receiver. In this arrangement, the endoscopic system isa completely self-contained wireless system.

[0057] Referring to FIG. 6, all embodiments described thus far includeda projection of the endoscope image onto the camera and observing theimage on the monitor or with other electronic means, e.g. head mounteddisplays. However, in many cases direct visualization through theendoscope is sufficient for the task (e.g., quick diagnosis, insertionof anaesthetic tube, industrial applications, etc). The rotational jointis no longer required since the entire system may be rotated withoutchanging the image orientation. An endoscope 343 is removably attachedto a solid-state light source assembly 344 designed similarly to theprevious embodiments. Solid-state light source assembly 344 includes abattery compartment 372 having a battery to power the light sources (notshown). Solid-state light source assembly 344 connects to an eyepiece373. The user looks into the eyepiece 373 and visually observes theimage. An optical system 374 provides for virtual image formationlocated at about 250 mm distally from eyepiece 373 suitable for visualobservation.

[0058] Referring to FIG. 7, in still other embodiments, a rigidendoscope has a housing 475 with a light post fitting 477 directed atabout 90° angle to a longitudinal axis 400 of the endoscope. Theendoscope has a standardized eyepiece 476 situated proximally to thebody 475. This embodiment can be easy to configure so as to retrofit theexisting population of endoscopes. Solid-state light source assembly 444is arranged so that it has a distal part 483 which receives a standardeyepiece 476 and locks it into place by a locking mechanism (not shown).Fiber fitting 452 is made external to the main body of the solid-statelight source 444. A short piece of light cable 478 connects theendoscope light post 477 and the illuminator end fitting 452. The lightcable 478, having a fiber bundle 479 and a protective jacket 482,includes female fittings 480 and 481 connected to illuminator endfitting 452 and endoscope light post 477 respectively. In otherembodiments, the solid-state light source is small enough to be attacheddirectly to the endoscope (e.g., connected to the light post or builtinto the proximal body of the endoscope).

[0059] Referring to FIG. 8, solid-state light sources 511 (e.g. whiteLEDs) are placed in a ring-like fashion directly at the distal end ofthe insertion section 505 of the endoscope. In an electronic endoscopeconfiguration, the image sensor 533 is located at the distal end of theinsertion portion. However, similar designs will also apply to theendoscopes with proximal location of the image (e.g., rod-lensendoscopes, fiberscopes). This embodiment is best suited for relativelylarge diameter endoscopes, for instance, 10 mm diameter endoscopes whichare standard in laparoscopy. These embodiments have high-resolutioncolor image sensors such as CCD or CMOS devices are available in smallsizes as small as {fraction (1/7)}″ format package (3.6 mm). Using smallimaging devices and small LED packages makes it possible to situate aring of LEDs at the distal end of a 10 mm endoscope around an objectivelens. The endoscope includes an outer tube 583, a distal housing 588 andan image sensor housing 589. Distal housing 588 houses an objective lens584. Objective lens includes a front lens 585, a middle lens 586 and aback lens 587. Front lens 585 usually in the shape of a negative lensfor the field of view expansion also serves as a front windowmaintaining the external seal. Alternatively, a separate flat window maybe arranged in front of the objective to maintain the seal. The housing588 at its periphery also contains a ring of LEDs 511. A transparentring 90 made of optical glass or optical grade sapphire is placed as aseal in front of LED ring to protect the LEDs from harsh surgical orindustrial environment. A partition 591 between ring 590 and the frontlens 585 of objective lens 584 prevents detrimental back reflectionsfrom the front surface of the ring 590 back into the objective 584. Afiberglass printed circuit board 592 is attached to the proximal end ofthe housing 588. Board 592 has openings 597 to receive positive andnegative LED leads that are passed through the openings and soldered toa positive and to a negative bus (not shown) respectively on theproximal side of the board 592. A cable 593 containing at least apositive lead 594 and a negative lead 595 which extends from theproximal portion of the endoscope and powers the LEDs 511. A slot 596 ismade in the image sensor housing 589 for the passage of cable 593.

[0060] Referring to FIG. 9, in other embodiments, electronic endoscopes,having an image sensor distally placed, can be incorporated to have alight source/fiber subassembly 609 in a handle 698. In addition, handle698 can house a focusing mechanism and a rotation mechanism for correctimage orientation. In this configuration, a retainer 699 secures lightsource/fiber subassembly 609 from the proximal side. The cable molding600 is attached to retainer 699. Cable molding 600 receives the electriccable 601 which is passed through the opening in light source/fibersubassembly 609 to the distal side. The fiber optic bundle 605 comingfrom the end fitting 652 extends to the distal end of the endoscope.Alternatively, a fiber-to-fiber or a fiber-to-light coupler joint may becreated at the distal end face of fitting 652. In other embodiments, abattery and wireless transmitter may be incorporated into the handle 698eliminating cable 601 making a wireless electronic endoscope containingno external light or electrical cables protruding from the handle.

[0061] Details relating to the semiconductor light sources (e.g., bothLED or laser) and the manner in which they are coupled to fiber opticalelements are described in U.S. patent application Ser. No. ______,Solid-State Light Source, in the name of Yuri Kazakevich, filed on Aug.31, 2001 and incorporated herein by reference.

[0062] U.S. Pat. No. 4,969,450, U.S. Pat. No. 5,797,836, and U.S. Pat.No. 5,575,757 are also incorporated herein by reference.

[0063] Still other embodiments are written within the scope of theclaims.

What is claimed is:
 1. An endoscopic system for internal inspection ofan object comprising: an endoscope extending along a longitudinal axisbetween a distal end to be inserted into the object and a proximal end;an illumination assembly attached to the proximal end of the endoscope,the illumination assembly including a solid-state light source; and anoptical system positioned distally from the solid-state light source,the optical system receiving and conveying light to the distal end. 2.The endoscopic system of claim 1 wherein the solid-state light sourceincludes a plurality of semiconductor light sources.
 3. The endoscopicsystem of claim 2 wherein the plurality of semiconductor light sourcesinclude light emitting diodes (LEDs).
 4. The endoscopic system of claim2 wherein the solid-state light source includes a hollow shaft having alongitudinal axis and a set of ribs positioned along a periphery of theshaft, each rib having a first side and a second side.
 5. The endoscopicsystem of claim 4 wherein the ribs extend along the longitudinal axis ofthe shaft and are symmetrically spaced around the periphery of theshaft.
 6. The endoscopic system of claim 5 wherein the first side ofeach rib has at least one LED and the second side of each rib has atleast one LED.
 7. The endoscopic system of claim 4 wherein each rib isaxially spaced along the longitudinal axis of the shaft.
 8. Theendoscopic system of claim 7 wherein each rib has at least two LEDsspaced symmetrical on the first side of each rib.
 9. The endoscopicsystem of claim 2 wherein the optical system includes a set of fiberoptic elements, each semiconductor light source is configured to emitlight to at least one corresponding fiber optic element.
 10. Theendoscopic system of claim 3 wherein the LEDs are grouped in a trio,each trio has a first LED configured to emit a blue light, a second LEDconfigure to emit a red light, and a third LED configured to emit agreen light.
 11. The endoscopic system of claim 1, further comprising: acamera system proximally positioned to the optical system; and afocusing system.
 12. The endoscopic system of claim 1 wherein theendoscope is removable and replaceable from the illumination assembly.13. The endoscopic system of claim 1, further comprising an eyepiecepositioned proximally to the optical system.
 14. The endoscopic systemof claim 9 wherein the endoscope includes a light post, the set of fiberoptic elements connect the solid-state light source to the light post.15. The endoscopic system of claim 14 wherein the endoscope includes aneyepiece.
 16. The endoscopic system of claim 15 wherein the light postis positioned to receive light at an angle to the longitudinal axis. 17.The endoscopic system of claim 1, further comprising a wirelesstransmitter positioned proximally from the distal end of the endoscopeand a battery positioned proximally to the distal end of the endoscope.18. The endoscopic system of claim 1, wherein the endoscope includes animage sensor.
 19. The endoscopic system of claim 1 further comprising animaging sensor positioned proximally to the endoscope.
 20. Theendoscopic system of claim 19 wherein the endoscope is configured torotate about the longitudinal axis of the elongated member relative tothe stationary imaging sensor.
 21. An endoscopic system for internalinspection of an object comprising: an endoscope extending along alongitudinal axis between a distal end to be inserted into the objectand a proximal end; and a solid-state light source positioned at theendoscope.
 22. The endoscopic system of claim 21 wherein the solid-statelight source is positioned in the distal end of the endoscope.
 23. Theendoscopic system of claim 21 wherein the solid-state light source ispositioned at the proximal end of the endoscope.